This invention relates to a rigidified, lightweight foam body for use as a dashboard for an automotive vehicle, or the like. The foam body is surrounded by a skin made of the same material, or of a thin foil material or by a skin formed from liquid media in the production mold for the foam body. The foam body has a rigid supporting insert. Molded parts project from a flat area of the body. Also, there are openings in the completed foam body permitting installation therein of various instruments and controls for the vehicle operator. Although this foam body is particularly useful as a dashboard for a motor vehicle, other uses may be apparent to persons skilled in the art.
A foam body can be reinforced by an insert which is comprised either of a soft, flexible or yieldable material, such as a glass fiber mat, or by a rigid material, such as metal or molded plastic. Typically, however, a foam body is not provided with both types of reinforcing inserts. Use of the different types of inserts yields foam bodies of greatly differing stability. The degree of stability, which is rather limited by the insert selected, cannot be optimally adapted to all of the various uses of these foam bodies.
German Allowed Application (Auslegeschrift) No. 28 54 544 describes a method for fabricating a fiber reinforced molded foam part. An attempt is made to attain adequate strength for the molded foam part with a minimum of material, so that even large-sized foam parts can be produced with sufficient strength and inherent stability. The difficulties of accomplishing this are great and the known solutions are complicated, as evidenced by the state of the art.
The serviceability of a molded foam part is greater when the reinforcement itself already has the required strength. Such a molded foam part is described in German Published Application (Offenlegungsschrift) No. 24 08 777, which concerns a dashboard for motor vehicles that includes a metal reinforcing insert. The metal insert extends over the full area of the dashboard. It can be given the necessary supporting capacity, which is the basis of the other previously indicated requirements, by selection of appropriate materials and by special designs.
The full-faced metal frames of the type disclosed in this German application have disadvantages, however, which particularly appear in the foam bodies used in the automobile industry. First, there is the weight of the frame. The metal framework adds about 2 kg. more weight in a medium sized car, compared to other reinforcements, such as a glass fiber framework. An adhesive joint between the foam (and also of a covering layer over the foam) and the metal framework is not readily possible. Therefore, bonding agents must be used or many openings must be provided in the metal plate to anchor the foam. Undercutting in the production mold is not possible because of the rigidity of the metal plate, which makes demolding difficult. To make an instrument panel, the insert also requires an easily moldable, deep-drawable and and therefore expensive insert material. The production mold for the one-piece metal part is large and thus expensive. In addition, long station times are required for the production of large pieces, as the initial inserts are frequently formed in several stages. One solution to this problem is to produce the insert from several parts. But, these small manufacturing advantages are offset by the fact that the various parts must first be joined with each other, primarily by welding.